Omicron cases in India neared the 600-mark as the case tally reached 578 on Monday. Delhi has recorded the maximum cases at 142 followed by Maharashtra with 141 cases, Kerala (57), Gujarat (49) and Rajasthan (43). Meanwhile, the registration for Covid-19 vaccination for children in the 15-18 year age group will open from January 1, 2022. Eligible children can register themselves on the CoWIN platform from January 1, 2022 and the vaccination drive will start from January 3.